The role of European chemical manufacturing companies in promoting effective communication of conditions of safe use by workers.

In 2006, the revised chemicals management legislation mandated that manufacturers of hazardous chemical substances conduct risk assessments for the entire substance life cycle. Additionally, they must communicate use-specific safe handling advice (exposure scenarios) to their customer, as annex to the Safety Data Sheet (SDS). Despite significant efforts to develop workable solutions for chemical mixtures, this goal has not yet been fully achieved. Therefore, a Cefic research project (LRI B23) was commissioned on how to ensure meaningful health risk communication for workers across supply chains. The research project determined that risk-based safe use advice generated by manufacturers, often does not reach the intended end-user and was seen as not tailored to specific user needs. Recipients of the advice are also not prepared to act based on information developed by suppliers. From an industry perspective, the complexity of supply chains and substance life cycles are considered major barriers for effective safe use communication. Exposure scenarios for substance use in industrial work environments are often perceived as adding little value compared to existing safe use arrangements required by other health, safety, and environmental legislation applicable to employers and duty-holders. To attain meaningful use-specific safe handling advice for workers, including those at non-industrial premises who may benefit most from such advice, knowledge transfer and close collaboration between manufacturers and formulators remain key elements, supported by enhanced regulatory appreciation.

Chemical Risk Assessment Screening Tool of a Global Chemical Company.

BACKGROUND: This paper describes a simple-to-use and reliable screening tool called Critical Task Exposure Screening (CTES), developed by a chemical company. The tool assesses if the exposure to a chemical for a task is likely to be within acceptable levels. METHODS: CTES is a Microsoft Excel tool, where the inhalation risk score is calculated by relating the exposure estimate to the corresponding occupational exposure limit (OEL) or occupational exposure band (OEB). The inhalation exposure is estimated for tasks by preassigned ART1.5 activity classes and modifying factors. RESULTS: CTES requires few inputs. The toxicological data, including OELs, OEBs, and vapor pressure are read from a database. Once the substance is selected, the user specifies its concentration and then chooses the task description and its duration. CTES has three outputs that may trigger follow-up: (1) inhalation risk score; (2) identification of the skin hazard with the skin warnings for local and systemic adverse effects; and (3) status for carcinogenic, mutagenic, or reprotoxic effects. CONCLUSION: The tool provides an effective way to rapidly screen low-concern tasks, and quickly identifies certain tasks involving substances that will need further review with, nevertheless, the appropriate conservatism. This tool shows that the higher-tier ART1.5 inhalation exposure assessment model can be included effectively in a screening tool. After 2 years of worldwide extensive use within the company, CTES is well perceived by the users, including the shop floor management, and it fulfills its target of screening tool.

Risk assessment of silicosis and lung cancer among construction workers exposed to respirable quartz.

OBJECTIVES: The aim of this study was to assess the magnitude of the silicosis and cancer risk among construction workers. METHODS: In 1998, 1335 of 4173 invited construction workers with expected high cumulative exposure to quartz were studied for early signs of silicosis. In 2002 the study was repeated for 96 persons. Exposure measurements were performed among 34 construction workers. Silicosis risk was assessed by converting study results to the whole group of construction workers and by risk analysis based on exposure data combined with documented exposure response relations. Excess risk for cancer was also calculated from available exposure measures. RESULTS: The initial study among construction workers revealed a prevalence of 0.8% of workers with rounded opacities on chest X-rays. The follow-up showed a much higher percentage (12%) of persons with rounded opacities on X-rays. The results were confirmed by high-resolution computed tomography. It was estimated that roughly 9% of the population initially studied (N = 1335) would have been observed with rounded opacities at follow-up. On the basis of the exposure data, a lifetime risk of silicosis above 5% is expected for workers exposed to levels above the occupational exposure limits. An excess lifetime risk for lung cancer is expected when workers are exposed to quartz levels above the occupational exposure limit. Due to the scarcity of exposure data, an estimation of the size of the group at risk is not yet possible. CONCLUSIONS: All available data indicate that construction workers exposed to quartz levels above occupational exposure limits are clearly at elevated risk of silicosis and other respiratory diseases.

Variability in quartz exposure in the construction industry: implications for assessing exposure-response relations.

The aims of this study were to determine implications of inter- and intraindividual variation in exposure to respirable (quartz) dust and of heterogeneity in dust characteristics for epidemiologic research in construction workers. Full-shift personal measurements (n = 67) from 34 construction workers were collected. The between-worker and day-to-day variances of quartz and respirable dust exposure were estimated using mixed models. Heterogeneity in dust characteristics was evaluated by electron microscopic analysis and electron spin resonance. A grouping strategy based on job title resulted in a 2- and 3.5-fold reduction in expected attenuation of a hypothetical exposure-response relation for respirable dust and quartz exposure, respectively, compared to an individual based approach. Material worked on explained most of the between-worker variance in respirable dust and quartz exposure. However, for risk assessment in epidemiology, grouping workers based on the materials they work on is not practical. Microscopic characterization of dust samples showed large quantities of aluminum silicates and large quantities of smaller particles, resulting in a D(50) between 1 and 2 microm. For risk analysis, job title can be used to create exposure groups, although error is introduced by the heterogeneity of dust produced by different construction workers activities and by the nonuniformity of exposure groups. A grouping scheme based on materials worked on would be superior, for both exposure and risk assessment, but is not practical when assessing past exposure. In dust from construction sites, factors are present that are capable of influencing the toxicological potency.

Lung function decrease in relation to pneumoconiosis and exposure to quartz-containing dust in construction workers.

BACKGROUND: Prevalence of exposure related respiratory symptoms and decreases in lung function are unknown among quartz dust exposed construction workers. METHODS: In a cross-sectional study (n = 1335), the occurrence of respiratory symptoms, was recorded and spirometric lung function was measured. Results were associated with exposure data and presence of radiographic abnormalities and compared with a reference population. RESULTS: Pneumoconiosis (profusion category 1/1 or greater) was associated with increased risks of FEV(1) and FVC values in the lowest 5% group, and with group-based decreases of 270 ml/s and 180 ml, respectively. Average lung function of construction workers was somewhat lower compared to a Dutch reference population. Lung function was not associated with exposure, except for a reduction in FVC of 5 ml per year for those with higher exposure. CONCLUSIONS: In quartz dust exposed construction workers obstructive and restrictive lung function loss was detected.

Dust control measures in the construction industry.

Quartz is a human carcinogen and a causative agent of silicosis. Exposure levels often exceed exposure limits in the construction industry. The need for effective control measures is high, but the complex structure of the construction industry, the variability in sources of exposure and the frequent changes of worksite makes it difficult to implement even simple and potentially effective control measures. The aim of this study was to evaluate the impact of control measures for reducing quartz dust exposure and to assess the extent of their use. Full-shift respirable dust measurements (n = 61) and short-term measurements among construction workers were performed and results of a questionnaire study among 1335 construction workers were analysed. Full-shift measurements showed respirable quartz exposure levels up to 63 times the maximum allowable concentration (MAC) value (0.075 mg/m(3)). More than half of the measurements were above the MAC value. Control measures were not very strongly associated with the full-shift exposure estimates, but the short-term measurements showed large reduction factors (>70%) when wet dust suppression or local exhaust ventilation was used. The effectiveness of control measures is potentially high, and a significant part of the construction worker population is indeed using them on a regular basis. Still, both the exposure study and questionnaire survey show that the use of respiratory protection is the most widely used preventive measure in the construction industry. Respiratory protection might not always reduce exposure sufficiently. Only the combined use of more than one control measure can reduce exposures to acceptable levels.